Hi, does anyone know how to adjust the main beam aim,I have one very low and one very high, the bulb holder is also very unusual, as it seems to be a simple push fit in the headlamp, any help would be much appreciated.

If you've just replaced a lamp, it may be that you haven't seated it correctly.
The fitting is H7, this has a tab coming off the baseplate (at 12 o'clock) with two dimples (at approx 8 and 4 o'clock).
When you remove the plug from the back of the lamp, you can then swing the two clips up or down depending on main or dipped beam.
the tab sits in between the two ends of the clip, the dimples allowing each side of the clip to locate.
iirc, on dip, the tab should be at 12 o'clock and on main the tab should be at 6 o'clock.
Even ensuring the tab is in the right place, you still need to ensure the base of the lamp is seated flat in the holder.